Banned outfit ULFA has warned ONGC and Oil India Limited (OIL) to desist from carrying out seismic exploration of hydrocarbons in the Brahmaputra valley in the interests of safeguarding historic monuments, archaeological sites and environment of the state as a whole. The ULFA' warning has given a new twist to the raging controversy shrouding the seismic exploration, which has allegedly caused damage to a number of historical sites and monuments in Upper Assam district of Sivasagar. In an article in the latest issue of its mouthpiece, "Freedom', the soft copy of which has been e-mailed to the media here, the ULFA has warned of resistance to the ongoing seismic explorations carried out by the ONGC in the district "putting a number of historic monuments and archaeological sites in peril'. The ULFA has called upon the ONGC to heed to the public protests by local people in the affected areas and stop the seismic exploration immediately. The outfit has warned of mobilising mass resistance if the ONGC continues with its seismic exploration operations that have "caused damages to age-old monuments from Ahom dynasty in Sivasagar district' besides inflicting damages to private property in many areas. The outfit has also called upon the OIL to abandon its plans to go for a seismic exploration of the Brahmaputra basin in search of crude oil and natural gas to avoid catastrophic impact on the ecology.